1. The soil bacterium Bradyrhizobium japonicum is an agriculturally important microorganism as it is the microsymbiont of soybean, the second most valuable crop plant in the U.S. behind corn. In addition to the use in food industry, soybean accounts for 80% of biodiesel production in the U.S. Clearly, there has been an increase in demand for more soybean production. Although there are several practical approaches to achieving increased production and crop yields, ranging from optimization of the use of chemical nitrogen fertilizers to development of genetically engineered herbicide-tolerant and/or insect-resistant soybeans, little is focused on fundamental improvement of nitrogen fixation by B. japonicum whose culture has been applied as inoculants (i.e., biological fertilizers) to the field. To improve inoculant performance and optimize the benefits of biological nitrogen fixation, it is important to fully understand how B. japonicum responds to alterations in the soybean root environment (rhizosphere). The objective of this project is to reveal global gene expression and relevent metabolites of B. japonicum that responds physiologically and metabolically to chemical cues released into the soybean rhizosphere by the plants using functional genomics such as RNA-seq and metabolomics. Dr. Chang is also going to employ a culture-independent metagenomic and metatranscriptomic approaches to increase our understanding of how rhizobial communities, rather than a species, interact with legume plants.

2. Microbial biofilm (specifically unsaturated biofilm) in several Pseudomonas strains is the other area of interest. Infection of medical devices is caused by formation of bacterial biofilms on the surface of the device. Biofilms on medical devices are the source of major challenges for medical settings because bacteria within biofilms are a lot more resistant to antibiotics compared to the free floating or planktonic bacteria. In general, the best way of fighting with biofilms is early detection and prevention of biofilm formation in the first place, which requires sensitive sensors. Therefore, in collaboration with UT-Dallas (Dr. Minary) and UNTHSC (Dr. Simecka), there is a pressing need for development of sensors that can sense the biofilm formation in very early stages. In addition, Dr. Chang has tried to understand how the molecular mechanism is involved in unsaturated biofilm formation and development.

This course is intended to provide students with an overview of different techniques used during manipulation of microorganisms. It will allow students to gain a historical perspective of techniques used in microbiology (e.g., Winogradsky column) as well as learn state of the art molecular characterization of microorganisms and their genetic manipulation.

Office Hours

This course is intended to provide students with an overview of different techniques used during manipulation of microorganisms. It will allow students to gain a historical perspective of techniques used in microbiology (e.g., Winogradsky column) as well as learn state of the art molecular characterization of microorganisms and their genetic manipulation.

Service to the Community

Volunteered

2012 to
PresentRhizobium project

"Rhizobium project" to study how efficiently rhizobial strains can be applied as an inoculant in soils and rhizospheres. This project has been conducted with Fort Towson High School students Lane Johnson, Trenton Cadle, Brody Pettyjohn, Amy Burkhalter, and Mecaela Church and Teacher Niccole Rech and Dr. James Heitholt at Texas A&M-Comerce.

Service to the Profession

Elected

Jan 2014 to
PresentEditor

Journal of Microbiology

2013 to
PresentAdvisory Committee

The 22th North American Conderence on Symbiotic Nitrogen Fixation (NACSNF), University of Minnesota

Jan 2013 to
PresentEditorial Board

Applied and Environmental Microbiology

2012 to
PresentFuture Development Advisory Committee

The Microbioogical Society of Korea (MSK)

Appointed

May 2013 to
PresentOrganizer

The 2013 International Meeting of the Microbiological Society of Korea (MSK), Republic of Korea, May 2013

May 2013 to
PresentConvener

The Nobel Lecture by Dr. Robert Huber, a Nobel Prize Awardee in Chemistry in 1988. Translation of his lecture, questions and answers to the audience, Republic of Korea, May 2013.

Honors student project, several students (currenlty, Vivian Nguyen), Honors College

2008 to
PresentAdvertising

Advertisement of UTA graduate school to more than 17 foreign institutions. This also includes introduction of UTA and benefit of studying abroad at UTA. This activity has been supported by UTA graduate school.